Walking, standing up from a chair, turning, and leaning are important for being able to move around independently. Gait speed, the time it takes to stand up out of a chair, and the ability to stand with one foot in front of the other (tandem stance) help predict an older person's ability to do daily and other activities such as shopping, traveling, and cooking.
Some elements of gait normally change as people get older; others do not.
Speed of walking (gait velocity) remains the same until about age 70, and then it slows down. Speed of walking is a powerful predictor of mortality—as powerful as the number of chronic medical conditions and hospitalizations a person has. At age 75, slow walkers die 6 years or more before walkers with a normal speed and 10 years or more before fast walkers.
Speed of walking slows because older people take shorter steps. The most likely reason for shortened step length (the distance from one heel strike to the next) is weakness of the calf muscles. Calf muscles propel the body forward, and calf muscle strength declines with age. However, older people seem to compensate for decreased calf strength by using their hip flexor and extensor muscles more than young adults.
Cadence, which is the number of steps taken in a minute, does not slow down with age. Every person has a preferred cadence, which is related to leg length. Tall people take longer steps at a slower cadence; short people take shorter steps at a faster cadence.
Double stance is the term given for when both feet are on the ground during the process of taking a step. This phase of a step is a more stable position for moving the center of mass forward than when only one foot is on the ground. The percentage of time spent in double stance increases with age. Older people may increase time spent in double stance even more when they walk on uneven or slippery surfaces, when they feel off-balance, or when they are afraid of falling. They may appear as if they are walking on slippery ice.
Walking posture changes only slightly with aging. Older people walk upright, with no forward lean. However, older people walk with more downward rotation of the pelvis and with an increased curve of the lower back (called lumbar lordosis). Usually, weak abdominal muscles, tight hip flexor muscles, and increased abdominal fat contribute to this change in posture. Older people also walk with their legs rotated laterally (toes out) about 5 degrees, possibly because of a loss of hip internal rotation or in order to increase stability. Foot clearance in swing is unchanged with age.
Joint motion changes slightly with age. Ability of the foot to flex is reduced during the late stage of stance (just before the back foot lifts off). The overall motion of the knee is unchanged. Hip flexion and extension are unchanged, but the hips have increased adduction. Adduction brings the hips toward the midline of the body. Pelvic motion is overall reduced.
A number of disorders can contribute to a dysfunctional or unsafe gait. A gait can be abnormal in various ways and certain types of abnormalities help doctors understand what is causing the gait problem.
Asymmetry: When healthy, a person’s body moves symmetrically while walking (motions are equal on the right and left sides). If a person consistently does not have symmetry while walking, often the cause is a one-sided issue, for example, a limp caused by a painful ankle. If the reason for the lack of symmetry is not obvious, the cause may be a problem with the brain or use of certain drugs.
Difficulty starting or continuing to walk: Older people may have difficulty starting or continuing to walk. When they start to walk, their feet may appear stuck to the floor, typically because they do not shift their weight to one foot to allow the other foot to move forward. Doctors may look for a movement disorder, such as Parkinson disease, to find the cause of this gait problem. Once gait is started, a person's steps should be continuous, with little variability in the timing of the steps. Freezing, stopping, or almost stopping usually suggests a cautious gait, a fear of falling, or a problem with the frontal lobe of the brain. Scuffing the feet is not normal (and is a risk factor for tripping).
Retropulsion: Retropulsion is when a person unintentionally steps backward when trying to start walking or falls backward while walking. Doctors may look for a problem with the front lobes of the brain, parkinsonism, syphilis,small strokes, or progressive supranuclear palsy as the possible cause.
Footdrop: Footdrop is difficulty lifting the front part of the foot because of weakness or paralysis of the muscles involved. A person's toe drags when taking a step. To avoid catching the toe, people with a dropped foot may lift their leg higher than normal during a step.
Short step length: Short step length may be caused by a fear of falling or by a nerve or muscle problem. The leg with the short step is usually the healthy one, and the short step is usually due to a problem during the stance phase of the opposite (problem) leg.
Increased step width: As gait speed decreases, step width increases slightly. A wide-based gait can be caused by disease in the knees or hips or in the brain's cerebellum. Variable step width (lurching to one or both sides) may be due to poor muscle control because of a problem in the brain.
Circumduction: People with pelvic muscle weakness or difficulty bending the knee may move their feet in an arc rather than a straight line when stepping forward. The arcing movement is called circumduction.
Festination: Festination is a progressive quickening of steps (usually while leaning forward) that can cause a person to break into a run to prevent falling forward. Festination can occur in people with Parkinson disease and rarely as a side effect of dopamine-blocking drugs.
Trunk lean: A person whose trunk leans sidewards may be compensating for joint pain due to arthritis or foot drop.
Doctors try to determine as many potential contributing factors to gait disorders as possible by
Discussing the person’s complaints, fears, and goals related to mobility
Observing gait with and without an assistive device, such as a cane or walker (if safe)
Assessing all components of gait (initiation of gait, right step length and height, left step length and height, symmetry)
Observing gait again with a knowledge of the person’s gait components
Doctors do a physical examination and ask open-ended questions regarding any difficulty with walking, balance, or both, including whether the person has fallen (or fear they might fall). The doctor also asks about specific capabilities, such as whether the person can go up and down stairs; get in and out of a chair, shower, or tub; and walk as needed to buy and prepare food and do household tasks. They will assess the person's muscle strength, especially in the calves and thighs.
High levels of physical activity help older people maintain mobility, even in people with disease. Regular walking or maintaining a physically active lifestyle is critical to keeping a healthy gait. The adverse effects of being inactive cannot be overstated. A regular walking program of 30 minutes each day is the best single activity for maintaining mobility; however, walking will not increase strength in a person who is weak. Including hills during the walk can help maintain leg strength. The use of canes or walking sticks that are adjustable can provide confidence and safety for older adults.
A gait disorder does not always need to be treated or improved. A slow, abnormal gait may help an older person walk safely and without assistance. However, doctors may offer to treat a person's gait to help improve quality of life. Treatments include exercise, balance training, and assistive devices.
Frail older people with mobility problems may improve with an exercise program. Walking or strength (resistance) training may reduce knee pain and improve gait in people with arthritis. Resistance exercises can improve strength, especially if the person is frail and has a slow gait. People usually need two or three training sessions a week until reaching their strength goal. Using good form during each exercise is important to reduce soreness or injury. A combination of leg press machines (or alternatively chair rises with weight vests or weights attached to the waist), step ups, stair climbing, and knee extension machines may be recommended to strengthen all the large muscle groups involved in walking.
Many people with balance problems improve with balance training. First, health care professionals help teach people a good standing posture and balance while standing still. People are then taught to be aware of the location of pressure on their feet and how the location of pressure moves with slow leaning or turning to look to the left or right. People also practice leaning forward (using a wall or counter for support), backward (with a wall directly behind), and to each side. The goal is to be able stand on one leg for 10 seconds.
Balance training can also be more dynamic. Dynamic balance training can involve slow movements in a single stance, simple tai chi movements, tandem (heel to toe) walking, turns while walking, walking backward, walking over a virtual object (for example, a stripe on the floor), slow forward lunges, and slow dance movements.
Canes are particularly helpful for people with pain caused by knee or hip arthritis or with peripheral neuropathy of the feet because a cane transmits information about the type of surface or floor to the cane-holding hand. A "quad cane" can stabilize the patient but usually slows gait. Canes are usually used on the side opposite the painful or weak leg. Many store-bought canes are too long but can be adjusted to the correct height (see figure Just the Right Height).
Walkers can reduce the force and pain at an arthritic joint more than a cane, assuming adequate arm and shoulder strength. Walkers provide good stability and moderate protection from forward falls but do little or nothing to help prevent backward falls for people with balance problems. When prescribing a walker, a physical therapist considers the sometimes competing needs of providing stability and maximizing walking efficiency. Four-wheeled walkers with larger wheels and brakes maximize efficiency but provide less stability.